John miller



(N Model.) l

. J. MILLER.- v i GRINDIVNGDEVIGE POR-'ROTARY G-UTTERS. No 531,547.

Patented'neo. 25,1894.

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UNITED STATES PATENT OFFICE.

JOHN MILLER, OENEWTON, NEW JERSEY, AssIGNOR OE Two-TrnR-Ds To JOHN HUsToN AND IRA o. MOORE, OE sAME PLACE.

i'GRlNDING DEVICE FOR ROTARY CUTTERS.

SPECIFICATION forming part of Letters Patent No. 531,547, dated December 25, 1894. Application tiled March 12, 1894. .Serial No, 503,299. (No model.)

To @ZZ whom it may concern.-

Be it known that I, JOHN MILLER, a citizen of the United States, residing at Newton, in the county of Sussex and State of New Jersey, have invented certain ne'w and useful Improvements in Grinding Devices for Rotary Cutters; and I do hereby declare the following Vto be a full, clear, andexact description ofthe invention, such as will enable others skilled in the art to which it appertains to make and use the same.

My invention relates to improvements in grindingdevices for rotary-cutters orsimilar tools.

The invention will first be described inconnection with the accompanying drawings, and then particularly pointed outin the claims.

In the drawings-Figure 1 is a plan view of i a grinding device embodying my invention.

Fig. 2 is a front elevation of the same. Fig. 3 is a side elevation of the same. Fig. 4 is a Vertical section through the center of the tool holder. Fig. 5 is a horizontal section showing the ratchet. Fig. 6 is a detail view ofthe sleeve. l l

Referring Vto the drawings, 1 is anordinary arbor, journaled at 2 and provided with a pulley/3 by which it is revolved. On the end of the arbor is fixed an emery wheel 4 or similar grinding device. To the frame 5 which supports the journal boxes 2 is attached an arm 6, which is slotted at its outer end at 7. In this slot is secured a ratchet case8by means of astud 9 fixed to the bottom of the ratchetcase, this stud 9 entering the slot 7 and being secured to the arm by a nut 10 and washer 11, the stud being thus held from movement in the slot when the nut 10 is tightened.

To the top of the ratchet case 8 is secured a cap 12 by means of screws 13, the cap having a central opening through which projects a tool arbor 14 fixed to a ratchet-wheel 15, the latter being located within the ratchet-case 8. The ratchet-teeth of the ratchet-Wheel 15` are arranged to be'engaged by a pawlor dog 16, which is movable in a recess in the ratchetcase and is fixed to a pawl-rod 17, the latter projecting outside the ratchet-case where it is provided with a milled head 18. The pawl is held into engagement with the teeth on the ratchet-'wheel by means of a spring 19, which surrounds the pawl-rod 17', as will be plain from the drawings.

That portion of the tool-arbor which projects above thecap 12 is slotted, as at 20, and on this portion of the said arbor is mounted a sleeve 21provided with a spline or feather 22 which enters the slot 20 in the tool-arbor, thus permitting the sleeve, 21, to move up and down on the arbor yet compelling the arbor to rotate when the sleeve is turned.

The sleeve has a squared portion'23, a cylindrical central portion 24, on which the tool tobe ground is placed, and a screw-threaded end 25 Onto which is screwed a nut 26, preferably milled on the edge, as shown.

The operation of my device is as follows: The rotary cutter to be sharpened is placed on the sleeve, as shown at 2 7, and the nut 26 screwed down so as to clamp the cutter against the shoulder formed by the top of the squared portion 23. While this is being done the sleeve is held at the upper end of Athe tool arbor, and as soon as the rotary cutter to be ground is fixed to the sleeve the emery wheel vis set in motion by power from any suitable source. The sleeve is then allowed lto drop down gradually on the tool-arbor, the edge of the emery Wheel entering the proper space between'the bits of the cutter and grinding the side of the approximate bit. The sleeve is then raised with the cutter until the latter is clear of the emery-wheel, whereupon the sleeve and with it the arbor is rotatedone tooth of the ratchet-wheel, which can be determined by the clicking of the pawl. The sleeve is rotated by means of the squared portion 23 which is grasped by the operator. The number of teeth on the ratchet-Wheel is equal tothe number of bits or teeth on the cutter, and therefore when the tool arbor is rotated one tooth'of the ratchet-Wheel, the next tooth or bit of thev cutter is brought into its proper position for contact with the revolving emery-wheel, whereupon the sleeve is moved downward'until the second tooth of the cutter Yis sharpened the operation being repeated as before until'the whole cutter is sharpened. By means of the stud 9, slot' 7 and nut 10 the tool-holder may be adjusted roo i i MWI with relation to the einery-wheel in order to compensate for the wearing of the emery- Wheel.

Having thus fully described my invention, what I claim as new, and desire to secure by Letters Patent, isM

l. In arotary-tool grinding-device, the combination, with a slotted tool-arbor, a ratchetwheel Iixed thereon, and a spring-pawl in engagement with the ratchet-wheel, of a sleeve mounted on the tool-arbor and provided with a feather engaging the slot in the arbor, and a nut threaded onto the end of the sleeve, substantially as described.

2. In a rotary-tool grinding-device, the combination, with a grinding Wheel, an arbor on which the Wheel is fixed, means for revolving the arbor, a frame in which the arbor is jour- JOHN MILLER.

XVtnesses:

LEWIS SAM BLASCOM, DAVID B. IIETZEL. 

